GNS Science has dropped the odds of a magnitude 7 or greater earthquake in the next month to 24 percent, down from 30 percent. But it says people should still be braced for large aftershocks, with a 95 percent chance of a quake of a magnitude 5 to 5.9 over the next day.

Key facts:

A 7.8 magnitude earthquake at a depth of 15km struck near Hanmer Springs at 12.02am on Monday.

There have been two confirmed deaths and more than 20 injuries.

The inland road route into Kaikoura has been partially re-opened, for military vehicles.

Emergency services are aware of the risk of another earthquake and are "ready to go" in Wellington, Fire Service spokesperson Brendan Nally says.

Related Stories

The central city was reopened for business on Tuesday - just one day after what we now know was one of the three biggest earthquakes to hit New Zealand in over a century. The Civil Defence Minister… Audio